Electron locking in layered structures by a longitudinal magnetic field

dWe describe a state of electrons and phonons arising in layered structures , like cuprates and semiconductor superlattices due to electron-phonon inte ractions which are strongly enhanced by a strong magnetic field. These stat es are characterized by a localization of phonons and a self-trapping or lo cking of electrons in one or several quantum wells (layers) due to an addit ional, deformational and/or polarizational potential arising around these l ocking wells (layers). Using the tight-binding and adiabatic approximations the whole energy spectrum of such self-trapped states is found. Finally, w e discuss possible experiments which may detect these predicted self-trappe d states, [S0163-1829(99)00934-0].